Combustion wave ignition for combustors

ABSTRACT

A system, such as a turbine power production system, including a plurality of combustion chambers. The combustion chamber may be provided with an ignition system that allows for substantially simultaneous ignition of each of the plurality of the combustors. Generally, a detonation wave may be provided to each of the combustion chambers substantially simultaneously from a single ignition combustion wave chamber.

FIELD

The present invention relates generally to gas powered turbines forgenerating power, and more particularly to a substantially simultaneousignition of a plurality of combustors of a gas powered turbine system.

BACKGROUND

It is generally known in the art to power turbines with gases beingexpelled from combustion chambers. These gas powered turbines canproduce power for many applications such as terrestrial power plants. Inthe gas powered turbine a fuel is combusted in an oxygen richenvironment. The fuel may be any appropriate fuel such as a liquid orgas. Exemplary fuels include hydrocarbons (for example methane orkerosene) or hydrogen. Generally, these combustion systems may emitundesirable compounds such as nitrous oxide compounds (NOX) and carboncontaining compounds. It is generally desirable to decrease variousemissions as much as possible so that selected compounds may not enterthe atmosphere. In particular, it has become desirable to reduce NOXemissions to a substantially low amount. Emissions of NOX are generallydesired to be near zero, and are accepted to be near or at zero, if theyare equal to or less than about one part per million volume of dryweight emissions.

A combustion chamber fuel, such as methane, is combusted in atmosphericair where temperatures generally exceed about 1427° C. (about 2600° F.).When temperatures are above 1427° C., the nitrogen and oxygen compounds,both present in atmospheric air, undergo chemical reactions whichproduce nitrous oxide compounds. The energy provided by the hightemperatures allows the breakdown of dinitrogen and dioxygen, especiallyin the presence of other materials such as metals, to produce NOXcompounds such as NO₂ and NO.

It has been attempted to reduce NOX compounds by initially heating theair before it enters the combustion chambers to an auto-ignitiontemperature. If the air enters the combustion chamber at anauto-ignition temperature, then no flame is necessary to combust thefuel. Auto-ignition temperatures are usually lower than pilot flametemperatures or the temperatures inside recirculation flame holdingzones. If no flame is required in the combustion chamber, the combustionchamber temperature is lower, at least locally, and decreases NOXemissions. One such method is to entrain the fuel in the air before itreaches the combustion chamber. This is done substantially continuouslythroughout operation of the combustor. The air or oxidizer must beheated with pre-burning to operate at all. This vitiated air, that isair which includes the fuel, is then ignited in a pre-burner to raisethe temperature of the air before it reaches the main combustionchamber. This decreases NOX emissions substantially. Nevertheless, NOXemissions still exist due to the initial pre-burning. Therefore, it isdesirable to decrease or eliminate this pre-burning, therebysubstantially eliminating all NOX emissions.

Although the air is heated before entering the main combustion chamber,it may still be ignited in the combustion chamber to combust theremaining fuel. Therefore, an additional flame or arc is used to combustremaining fuel in the main combustion chamber. Again the flame or arc isgenerally always required to maintain combustion. This reduces thetemperature of the igniter, but still increases the temperature of thecombustion chamber. In addition, no fuel is added to the air as itenters the combustion chamber. Rather all the fuel has already beenentrained in the air before it enters the combustion chamber to becombusted. This greatly reduces control over where combustion occurs andthe temperature in the combustion chamber.

Other attempts to lower NOX emissions include placing catalysts incatalytic converters on the emission side of the turbines. This convertsthe NOX compounds into more desirable compounds such as dinitrogen anddioxygen. These emission side converters, however, are not one hundredpercent efficient thereby still allowing NOX emissions to enter theatmosphere. The emission converters also use ammonia NH₃, gas to causethe reduction of NOX to N₂. Some of this ammonia is discharged into theatmosphere. Also, these converters are expensive and increase thecomplexity of the turbine and power production systems. Therefore, it isalso desirable to eliminate the need for emission side catalyticconverters.

Furthermore, it may be desirable to provide substantially simultaneousignition of a plurality of combustors. This may reduce undesirableemissions, while increasing longevity of the system. For example, ifonly a limited number of a selected number of combustors are ignited atonce and a combustion or shock wave is used to ignite the others,substantial back pressures and undesirable stresses may be exerted onthe system. Therefore, igniting each of the combustors substantiallysimultaneously may decrease the stress placed on the system and increasethe efficiency of the start up, thereby decreasing selected emissions.

SUMMARY

A device and system for providing substantially simultaneous ignition toa plurality of combustors. Generally, a plurality of combustors may beprovided in a selected system, such as a gas powered turbine. Each ofthe combustors combusts a selected amount of fuel in an oxidizer toproduce the expanding gases to power the gas powered turbine. The systemallows a substantially single spark, preburner, or chamber to combust aselected amount of fuel, which then propagates along a selected line toprovide a combustion wave to a selected combustor. The preburner allowsfor the formation of a wave, which as it propagates becomes a combustionwave, such that a selected fuel and oxidizer provided at a point in theline will be ignited by the combustion wave. Therefore, a plurality ofpilot flames may be produced by a single combustion chamber.

Further areas of applicability may become apparent from the detaileddescription provided hereinafter. It should be understood that thedetailed description, while indicating the various embodiments of theinvention, are intended for purposes of illustration only and are notintended to limit the scope of the disclosure of the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The present description may become more fully understood from theaccompanying drawings, wherein:

FIG. 1 is a perspective view of a gas powered turbine including acombustor in accordance with the present invention;

FIG. 2 is a partial cross-sectional perspective view of a singlecombustor;

FIG. 3 is a detailed, partial cross-sectional, perspective view of aportion of the heat exchanger;

FIG. 4 is a simplified diagrammatic view of the flow of air through thecombustion chamber according to a first embodiment of the presentinvention;

FIG. 5 is a schematic view of an ignition system for simultaneousignition of a plurality of combustors;

FIG. 6 is a detailed, cross-sectional view of a portion of the ignitionsystem of FIG. 5;

FIG. 7 is a detailed, partial cross-sectional, perspective view of aportion of the heat exchanger according to various embodiments;

FIG. 8 is a combustor according to a various embodiment; and

FIG. 9 is a detailed partial cross-sectional perspective of an injectorplate according to the embodiment of FIG. 8.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS

The following description of various embodiments is merely exemplary innature and is in no way intended to limit the invention, itsapplication, or uses. For example, although the following combustor andsystems are described in conjunction with a terrestrial gas turbine,each and/or all may be used in other systems. The pre-mixer and heatexchanger may be used in systems other than turbine systems. Also asimultaneous ignition system may be used in any appropriate combustionor turbine system.

Referring to FIG. 1, a gas powered turbine 10 in accordance with variousembodiments is shown. The gas powered combustion turbine 10 may use anyappropriate fuel that may be combusted and may expand to move portionsof the gas powered turbine 10 to produce power. The gas powered turbine10 also may include a compressor 12 that forces atmospheric air into thegas powered turbine 10. The gas powered turbine 10 may include severalcombustion chambers 14 for combusting the fuel in a selected oxidizer.The combusted fuel is used to drive a turbine 15 including turbineblades 16 which are axially displaced in the turbine 15. There aregenerally a plurality of turbine blades 16, however, the actual numberdepends upon various factors, such as the power the gas powered turbine10 is to produce. Only a single turbine blade is illustrated forclarity.

In general, the gas powered turbine 10 ingests atmospheric air, combustsa fuel in it, this produces expanding gases that power the turbineblades 16. Air may be pulled in and compressed with the compressor 12,which generally includes a plurality of concentric fans which growprogressively smaller along the axial length of the compressor 12. Thefans in the compressor 12 may be powered by a single axle. The highpressure air then enters the combustion chambers 14 where the fuel isadded and combusted. Once the fuel is combusted, it expands out of thecombustion chamber 14 and engages the turbine blades 16 which, due toaerodynamic and hydrodynamic forces, spins the turbine blades 16. Thegases form an annulus that spin the turbine blades 16, which are affixedto a shaft (not shown). Generally, there are at least two turbine blades16. One or more of the turbine blades 16 engage the same shaft that thecompressor 12 engages.

A start up or ignition system 18 is also provided. The ignition system18 generally includes a combustion wave premix chamber 20 and a pilotline 22. The ignition system 18 is illustrated here diagrammatically,for simplicity, and is discussed in detail herein. Nevertheless, theignition system 18 generally allows for ignition or start up of each ofthe combustors 14 of the plurality provided on the gas powered turbine10 for substantially simultaneous ignition of the gas powered turbine10.

The gas powered turbine 10 may be self-powered since the spinning of theturbine blades 16 also powers the compressor 12 to compress air forintroduction into the combustion chambers 14. Other turbine blades 16are affixed to a second shaft 24 which extends from the gas poweredturbine 10 to power an external device. After the gases have expandedthrough the turbine blades 16, they are expelled out through an exhaustport 26. It will be understood that the gas powered turbine 10 may beused for many different applications such as engines for vehicles andaircraft or for power production in a terrestrially based gas poweredturbine 10.

The gases that are exhausted from the gas powered turbine 10 includemany different chemical compounds that are created during the combustionof the atmospheric air in the combustion chambers 14. If only pureoxygen and pure hydrocarbon fuel, were combusted, absolutely completelyand stoichiometrically, then the exhaust gases would include only carbondioxide and water. Atmospheric air, however, is not 100% pure oxygen andincludes many other compounds such as nitrogen and other tracecompounds. Therefore, in the high energy environment of the combustionchambers 14, many different compounds may be produced. All of thesecompounds exit the exhaust port 26.

It is generally known in the art that an equivalence ratio is determinedby dividing the actual ratio of fuel and air by a stoichiometric ratioof fuel to air (where there is not an excess of one starting material).Therefore, a completely efficient combustion of pure fuel and oxygenwould equal an equivalence ratio of one. It will be understood thatalthough atmospheric air in a hydrocarbon fuel may be preferred foreconomic reasons other oxidizers and fuels may be provided. The air mayprovide an oxidizer for the fuel.

It will be understood that the gas powered turbine 10 may include morethan one combustion chamber 14. Any reference to only one combustionchamber 14, herein, is for clarity of the following discussion alone.Various embodiments may be used with any oxidizer or fuel that is usedto power the gas powered turbine 10. Moreover, the combustor 14 maycombust any appropriate fuel. Air is simply an exemplary oxidizer andhydrocarbons an exemplary fuel.

The fuel that may be combusted in the gas powered turbine 10 may be anyappropriate fuel. The fuel may be liquid or gaseous depending uponvarious considerations and applications. In addition, the fuel may beany appropriate material that may be combusted in a selected oxidizer,such as oxygen and atmospheric air. For example, the fuel may be ahydrocarbon fuel such as methane, kerosene, synthesis gas (selectedmixtures of hydrogen and carbon monoxide), and other appropriatehydrocarbon fuels. In addition, the fuel may be hydrogen or otherappropriate fuels. The hydrogen may be formed in any appropriate mannerand provided to the gas powered turbine 10 to combust in the oxidizer topower the turbine blades 16.

With reference to FIG. 2, an exemplary combustion chamber 14 isillustrated. The combustion chamber may comprise any appropriatecombustion chamber such as the one described in U.S. patent applicationSer. No. 10/120,268 filed Apr. 10, 2002 entitled, “A Catalytic CombustorFor Substantially Eliminating Nitrous Oxide Emissions,” incorporatedherein by reference. The combustion chamber 14 may include a premixsection or area 30, a heat exchange or pre-heat section 32, generallyenclosed in a heat exchange chamber 33, and a main combustion section34. A first or premix fuel line 36 may provide fuel to the premix area30 through a fuel manifold 37 and a second or main fuel line 38 mayprovide fuel to the main combustion section 34 through a main injector52. Positioned in the premix area 30 is a premix injector 40 whichinjects fuel from the first fuel line 36 into a premix chamber orpremixer 42. Air from the compressor 12 enters the premix area 30through a plurality of cooling tubes 44 of a heat exchanger orpre-heater 45 (detailed in FIG. 3). The premix chamber 42 encompasses avolume between the premix injector 40 and an outlet of the cooling tubes44.

With further reference to FIG. 2, a plurality of catalytic heat exchangeor catalyst tubes 48 extend into the heat exchange area 32. The heatexchange tubes 48 are spaced laterally apart. The heat exchange tubes48, however, are not spaced vertically apart. This configuration createsa plurality of columns 49 formed by the heat exchange tubes 48. Eachheat exchange tube 48, and the column 49 as a whole, define a heatexchanger or catalyst pathway for air to travel through. The columns 49define a plurality of channels 50. It will be understood this is simplyexemplary and the tubes may be spaced in any configuration to form thevarious pathways. Extending inwardly from the walls of the heat exchangechamber 33 may be a directing fin 33 a. The directing fin 33 a maydirect the flow of air to the top and the bottom of the heat exchangechamber 33 so that air may be directed to flow through the channels 50defined by the heat exchange tubes 48. It will be understood by oneskilled in the art that any appropriate number of the directing fin 33 aand configuration may be used. It will also be understood that the fin33 a is not necessary and the air may be directed by hydraulic flow andthe heat exchanger chamber 33.

With continuing reference to FIG. 2 and reference to FIG. 3, near theends of the heat exchange tubes 48, where the heat exchange tubes 48near the main combustion section 34, is a main injector 52. The secondfuel line 38 provides fuel to the main injector 52 so that fuel may beinjected at the end of each heat exchange tube 48. Spaced away from themain injector 52, towards the premix area 30, is an intra-propellantplate 54. The intra-propellant plate 54 separates the air that istraveling through the channels 50 and the fuel that is being fed to thefuel manifold region 56 between the main injector face 52 and theintra-propellant plate 54. It will be understood, that theintra-propellant plate 54 is effectively a solid plate, though notliterally so in various embodiments and not illustrated here as a singlesolid plate. The placement of the heat exchange tubes 48 may dictatethat the intra-propellant plate 54 be segmented wherein one portion ofthe intrapropellant plate 54 is placed in each channel 50 between twocolumns 49.

Air that exits the heat exchange tubes 48 is entrained with fuelinjected from an injector port 60 in the main injector 52 and this fuelthen combusts in the main combustion section 34. The injectors 60 may beany appropriate injector or injector element. For example, the injector60 may be impinging injectors, such as those illustrated and describedin U.S. patent application Ser. No. 10/397,394, entitled “A CATALYTICCOMBUSTOR AND METHOD FOR SUBSTANTIALLY ELIMINATING NITROUS OXIDEEMISSIONS”, and commonly assigned and incorporated herein by reference.A further injector element that may be injector 60 includes the injectorelement described in U.S. patent application Ser. No. 10/729,679,entitled “A Fuel Injection Method and Apparatus for a Combustor”, andcommonly assigned and incorporated herein by reference. Therefore, theinjector 60 may be any appropriate injector and the above are merelyexamples of injectors that may be used in the combustor 14. The maincombustion section 34 directs the expanding gases of the combusted fuelto engage the turbine blades 16 so that the expanded gases may power theturbine blades 16.

A detailed portion of the heat exchanger 45 is illustrated in FIG. 3.Although, in various embodiments the heat exchanger 45 includes a largeplurality of tubes, as generally shown in FIG. 2, only a few of the heatexchange tubes 48 and cooling tubes 44 are illustrated here for greaterclarity. The heat exchanger 45 may be similar to that described in U.S.Pat. No. 5,309,637 entitled “Method of Manufacturing A Micro-PassagePlate Fin Heat Exchanger”, incorporated herein by reference. The heatexchanger 45 includes a plurality of the cooling tubes 44 disposedparallel to and closely adjacent the heat exchange tubes 48. Each of thecooling tubes 44 and the heat exchange tubes 48 may have a generallyrectangular cross section and can be made of any appropriate materialsuch as one having a generally good thermally conductivity. For example,the heat exchange tubes 48 and the cooling tubes 44 may be formed ofstainless steel. It will be appreciated that while the cooling tubes 44and the heat exchange tubes 48 are shown as being substantially square,the cross-sectional shape of the components could comprise a variety ofshapes other than square. Without being bound by the theory, it isbelieved that the generally square shape may provide a good thermaltransfer between the tubes 44 and 48.

Both the cooling tubes 44 and the heat exchange tubes 48 may be of anyappropriate size and may be generally square in cross-section having awidth and height of about 0.04 inches to about 1.0 inches (between about0.1 centimeters to about 2.5 centimeters). The thickness of the walls ofthe cooling tubes 44 and the heat exchange tubes 48 may be anyappropriate thickness. The walls may be strong enough to allow thefluids to flow through them, but still allow for an efficient transferof heat between the inside of the heat exchange tubes 48 and the air inthe channels 50 and cooling tubes 44. The thickness may also varyaccording to various reasons such as size and material choice.

The cooling tubes 44 extend parallel to the heat exchange tubes 48 for aportion of the length of the heat exchange tubes 48. As discussed above,the heat exchange tubes 48 generally define a pathway that may be acatalyst or heat exchange pathway. The cooling tubes 44 also define apathway that is generally a cooling pathway. The cooling tubes 44 mayalso define a portion of the heat exchange pathway as the oxidizer, suchas the compressed atmospheric air, travels past the heat exchange tubes48 through the heat exchanger 45.

Generally, each of the cooling tubes 44 is brazed to one of the heatexchange tubes 48 for the distance that they are placed adjacent oneanother. Moreover, the cooling tubes 44 and the heat exchange tubes 48may be brazed to an adjacent tube of the same type. The cooling tubes 44extend between the columns 49 of the heat exchanger tubes 48. Accordingto various embodiments, brazing materials are those with meltingtemperatures above about 538° C. (about 1000° F.). The cooling tubes 44extend between the columns 49 of the heat exchanger tubes 48. Thecooling tubes 44 and the heat exchange tubes 48, that may be brazedtogether, form the heat exchanger 45 that can provide asurface-to-surface exchange of heat. It will be understood, however,that air traveling in the channels 50 between the heat exchange tubes 48may also become heated due to the heat transferred from the heatexchange tubes 48 to the air in the channels 50.

Referring further to FIG. 3, according to various embodiments the fuelinjector ports 60 are formed in the main injector 52. The injector ports60 may be provided in any appropriate number. According to variousembodiments, there is a ratio of heat exchange tubes 48 to injectors 60of at least four to one. It will be understood, however, that anyappropriate ratio of the injectors 60 to the heat exchange tubes 48 maybe provided. The fuel is provided to the manifold region 56 which isbound by the intra-propellant plate 54, the main injector plate 52, anda manifold plate 61. The manifold plate 61 may underlay, overlay, orsurround the manifold region 56. This provides fuel to each of theinjector ports 60 without requiring an individual fuel line to eachinjector port 60. Therefore, as air exits each heat exchange tube 48,fuel is injected from the injector port 60 into the stream of airemitted from each heat exchange tube 48. In this way, the fuel can bevery efficiently and quickly distributed throughout the air flowing fromthe heat exchanger 45, as discussed further herein.

As discussed above, an ignition system 18 may be provided to allow anignition of the combustor 14. The ignition system 18 that includes thecombustion wave premix chamber 20 that allows for the transmission ofthe combustion wave along the ignition line 22 (a portion shown enlargedin FIG. 3 for clarity only) to a pilot port 62 that may be formed in themain combustion chamber 34. As illustrated particularly in FIG. 3, thepilot port 62 may extend a distance into the main combustion chamber 34.As described herein, a selected fuel and oxidizer may be transmitted tothe pilot port 62, such that the combustion wave may combust theoxidizer and fuel being provided to the pilot port 62. As mentionedabove and described further herein, although the oxidizer that exits thecatalyst tubes 48 is generally at an auto ignition temperature duringcertain periods and selected times of operation of the turbine 10 or thecombustor 14, the oxidizer may not have reached the auto ignitiontemperature. Therefore, it may be selected to provide the pilot port 62that may allow a pilot flame to assist in igniting the oxidizer and fuelmixture formed in the main combustion chamber 34. This allows thecombustion of the fuel in the main combustion chamber 34 even if theoxidizer being emitted from the catalyst tubes 48 has not yet reachedthe auto ignition temperature.

On the interior walls of each heat exchange tube 48 is disposed acoating of a catalyst. The catalyst may be any appropriate catalyst thatis able to combust or assist in combustion of the fuel, and may include,for example, platinum, palladium, or mixtures thereof. The catalyst isable to combust the fuel without the presence of a flame or any otherignition source. The catalyst is also able to combust the fuel withoutgenerally involving any side reactions. Therefore, the combustion of thefuel does not produce undesired products. It will be understood that ifthe fuel is not a hydrocarbon then the appropriate catalyst may bedifferent or the same. The catalyst allows combustion of the fuelwithout an additional heat source.

With continuing reference to FIGS. 1-3 and further reference to FIG. 4,a method of using the combustion chamber 14 according to variousembodiments will be described. The combustor 14 includes a pre-mixer 42which may be formed in any appropriate manner. The pre-mixer 42 mayinclude an open region, as illustrated in FIG. 4. The premixer 42 mayalternatively include any other appropriate structures. For example, thecooling tubes may extend into the premixer 42 and include orifices oroutlets that allow the oxidizer to exit into the premixer 42. It will beunderstood, therefore, that any appropriate structure may be provided inthe premixed chamber 42 that allows the oxidizer to mix with a selectedvolume of fuel before entering the catalyst tubes 48. When an openregion is used as the pre-mixer 42 the flow generally follows the pathindicated by the arrows in FIG. 4. It will also be understood that aplurality of tubes, as described above, are present in the heatexchanger, but have been removed for clarity in the present descriptionof the air flow.

Atmospheric air is compressed in the compressor 12 and then introducedinto the heat exchange chamber 33 at a high pressure. The air thatenters the heat exchange chamber 33 is directed by the directing fins 33a to the top and bottom of the heat exchange chamber 33 so that the airmay flow through the channels 50. The air that enters the heat exchangechamber 33 may be at a temperature of about 37° C. to about 427° C.(about 100° F. and about 800° F.). Generally, however, the air entersthe heat exchanger 45 at a temperature of about 204° C. to about 400° C.(about 400° F. to about 750° F.).

As the air travels in the channels 50, the air increases in temperatureto become “hot” air. The hot air flows through the pathway formed by thecooling tubes 44, which may also be referred to as a cooling tubepathway, and into the premix area 30. The hot air also receives thermalenergy while flowing through the cooling tubes 44. It will be understoodthat the cooling tubes 44 are adjacent a portion of the heat exchangetubes 48. The temperature of the hot air, as it enters the premix area30, may be about 427° C. to about 538° C. (about 800° F. and about 1000°F.). The air in the premix area 30 makes a turn within the premixchamber 42. As the air turns inside the premix chamber 42, the premixinjector 40 injects fuel into the air, entraining the fuel in the air.Again, any appropriate injector may be used to inject the fuel from thepremix injector 40 into the premixer 42. For example, a plurality ofports or a selected injector element may be provided to allow for theinjection of the fuel into the premixer 42. It will be understood thatany appropriate injector may be used. About 30% to about 60% of all thefuel used to power the gas powered turbine 10 is entrained in thismanner in the premix chamber 42.

After the air enters the premix chamber 42, it may flow out through thepathway formed by the heat exchange tubes 48. In the heat exchange tubes48, the fuel in the air combusts as it engages or reacts with thecatalyst that is disposed on the inside walls of the heat exchange tubes48. The catalyst may be disposed within the heat exchange tube 48 in aplurality of ways such as coating by painting or dipping or by affixingseals to the internal walls. As the fuel combusts, the temperature ofthe air may rise to about 768° C. to about 930° C. (about 1400° F. toabout 1700° F.). As the temperature of the air rises, it becomes highlyenergetic to form high energy air and may then exit the heat exchangetubes 48. The temperature that the high energy air reaches in the heatexchange tubes 48 is at least the hypergolic or auto-ignitiontemperature of the fuel being used in the gas powered turbine 10.Therefore, the high energy air that exits the heat exchange tubes 48 is,and may also be referred to as, hypergolic or auto ignition air. Theauto-ignition temperature of the air is the temperature that the air maybe at or above so that when more of the fuel is injected into thehypergolic air the fuel ignites automatically without any other catalystor ignition source.

Additional fuel is injected through the main injector 52 as the oxidizerexits the heat exchange tubes 48 and enters the main combustion section34. The fuel injected from the main injector 52 is injected through theinjector ports 60. Any ratio of injector ports 60 to heat exchange tubes48 may be used as long as all of the air exiting the heat exchanger 45is thoroughly mixed with fuel. Also, as discussed above, any appropriateinjector element or design may be used to mix the fuel with theoxidizer. Any additional fuel to power the gas powered turbine 10 isinjected at this point, such that fuel is added to the air at the premixchamber 42 and from the injector ports 60.

As the air travels through the heat exchange tubes 48, the fuel that wasentrained in the air in the premix chamber 42 may be at least partiallycombusted by the catalyst. This raises the temperature of the air fromthe temperature that it enters the heat exchange chamber 33. Inparticular, the temperature of the air may be raised to about 700° C. toabout 880° C. (about 1300° F. to about 1600° F.). This temperature, orthe selected temperature reached in the catalyst tubes 48, is generallythe hypergolic temperature of the fuel so that the fuel combustsspontaneously when added through the injector port 60. It will beunderstood that different fuels have different hypergolic temperatures.Therefore, the amount of fuel added in the premix section 42 may bealtered to determine the temperature of the air exiting the heatexchange tubes 48.

Returning reference to FIG. 3, the heat exchange tubes 48 extend from anupstream side 70 through the intra-propellant plate 54 and terminateinto the main injector 52. A face of the injector 52 a is downstream ofthe heat exchange tubes 48. Fuel may be provided through the main fuelline 38 to the manifold region 56 which is the area between theintra-propellant plate 54 and the main injector 52. Although only onemain fuel line 38 is illustrated, it will be understood that more thanone main fuel line may be provided. Formed in the main injector plate 52are oxidizer passages or pathways 72 which are extensions of the heatexchange tubes 48 formed in the main injector plate 52. The hypergolicair from the heat exchange tubes 48 passes through the oxidizer pathways72 and exits into the main combustion area 34. Extending back from theinjector port 60 may be a fuel injection path 74. Each fuel injectorport 60 may include at least one fuel pathway 74. The fuel pathway 74may be a bore formed in the main injector plate 52 to allow accessbetween the fuel manifold region 56 so that the fuel which is providedto the fuel manifold region 56 from the main fuel line 38 can reach thecombustion area 34. Generally, the fuel pathways 74 may be formed in themain injector plate 52 and the spaces or lands between the oxidizerpathways 72 which extend from the heat exchange tubes 48. Variouspathways 74 may be formed to achieve appropriate results, such as thosedescribed in U.S. patent application Ser. No. 10/729,595, entitled “ACatalytic Combustor and Method for Substantially Eliminating VariousEmissions”, incorporated herein by reference. Although any otherappropriate injector element may be used.

The injectors 60 may also allow a substantial intermixing of the fuelwith the air exiting the oxidizer pathways 72 before the fuel combustsso that the combustion in the combustion chamber 34, across the face of52 a of the main injector plate 52 is substantially even. This generallydoes not allow hot spots in the combustion area 34 to form, therebysubstantially eliminating the production of NOX chemicals.

During portions of operation the air that exits the heat exchanger 45may be at the auto-ignition or hypergolic temperature of the fuel usedin the gas powered turbine 10. Therefore, as soon as the fuel reachesthe temperature of the air, the fuel ignites. Since the fuel may bethoroughly mixed with the air, the combustion of the fuel is nearlyinstantaneous and may not produce any localized or discrete hot spots.Because the fuel may be well mixed with the air exiting the heatexchanger 45, there is no one point or area which has more fuel than anyother point, which could also create hot spots in the main combustionsection 34. Therefore, the temperature of the air coming from the maininjector 52 and into the main combustion section 34 is substantiallyuniform. During operation of the gas powered turbine 10, the fuel'scharacteristic mixing rate is faster than the combustion rate of thefuel.

The temperature of the air, after the additional fuel has been combustedfrom the main injector 52, may be about 1315° C. to about 1537° C.(about 2400° F. and about 2800° F.). Preferably, the temperature,however, is not more than about 1426° C. (about 2600° F.). Differentfuel to air ratios may be used to control the temperature in the maincombustion section 34. The main combustion section 34 directs theexpanding gases into a transition tube (shown in part extending from thecombustion section 34) so that it engages the turbine blades 16 in theturbine area 15 at an appropriate cross sectional flow shape.

The use of the heat exchanger 45 raises the temperature of the air tocreate hot or heated air. The hot air allows the catalyst to combust thefuel that has been entrained in the air in the premix chamber 42 withoutthe need for any other ignition sources. The catalyst only interactswith the hydrocarbon fuel and the oxygen in the air to combust the fuelwithout reacting or creating other chemical species. Therefore, theproducts of the combustion in the heat exchange tubes 48 aresubstantially only carbon dioxide and water due to the catalyst placedtherein. No significant amounts of other chemical species are producedbecause of the use of the catalyst. Also, the use of the heat exchangetubes 48, with a catalyst disposed therein, allows the temperature ofthe air to reach the auto-ignition temperature of the fuel so that noadditional ignition sources are necessary in the main combustion section34. Therefore, the temperature of the air does not reach a temperaturewhere extraneous species may be easily produced, such as NOX chemicals.Due to this, the emissions of the gas powered turbine 10 of the presentinvention has virtually no NOX emissions. That is, that the NOXemissions of the gas powered turbine 10 according to the presentinvention are generally below about 1 part per million volume dry gas.

Also, the use of the heat exchanger 45 substantially eliminates the needfor any other pre-burners to be used in the gas powered turbine 10. Theheat exchanger 45 provides the thermal energy to the air so that thecatalyst bed is at the proper temperature. Because of this, there are noother areas where extraneous or undesired chemical species may beproduced. Additionally, the equivalence ratio of the premix area isgenerally between about 0.20 and 0.30, while the equivalence ratio ofthe main injector 52 is between about 0.50 and about 0.60. This meansthat the fuel combustion will occur as a lean mixture in both areas.Therefore, there is never an excessive amount of fuel that is notcombusted. Also, the lean mixture helps to lower temperatures of the airto more easily control side reactions. It will be understood thatdifferent fuel ratios may be used to produce different temperatures.This may be necessary for different fuels.

The catalyst positioned in the catalyst tubes 48 may be able to combusta selected fuel at a selected temperature. At least, it will beunderstood that the catalytic activity of the catalyst may reach anoptimum or first order of reaction at a selected temperature, but mayinclude a less optimum reaction at a different temperature. For example,and not intended to be limiting, if the fuel is natural gas to power thegas powered turbine 10, the catalytic activity for various selectedcatalyst may be substantially below optimum or desired catalyticactivities at the temperature of the air that enters the catalytic tubes48 during start-up. That is during start-up, the temperature of the airreaching the catalytic tubes 48, as discussed above, is generally about37° C. and generally not greater than about 200° C. (98° F. to 390° F.).

The oxidizer that may be used to oxidize the fuel, so that the fuelcombusts, is atmospheric air that is drawn in through the compressor 12into the gas powered turbine 10. Although any appropriate oxidizer maybe used, such as liquid oxygen. The air may not be heated and issubstantially near room temperature or ambient temperature when the airis drawn in to be compressed with the compressor 12. Although the actionof being drawn in and compressed with the compressor 12 may increase thetemperature of the air, it still may not reach the optimal temperaturefor reacting the fuel with the catalyst. Therefore, it may be selectedto provide a start-up heating apparatus near the catalytic tubes 48. Forexample, electric coils or induction coils may be positioned around ornear the catalytic tubes 48 to heat the catalytic tubes 48 to a selectedtemperature. In addition, the air that is compressed with the compressor12 may be heated to a selected temperature to react with the catalyst inthe catalytic tubes 48.

Alternatively, or in addition to heating the air before it enters thecatalytic tubes 48, particularly at start-up, a fuel that may have ahigher kinetic energy on the catalyst on the catalytic tubes 48 may beused at start-up to achieve a selected temperature of the catalytictubes 48. For example, hydrogen gas may be used during start-up to powerthe gas power turbine 10. As discussed above, hydrogen may be the fuelthat is selected to combust in the oxidizer. In addition, two fuels maybe used during a single operating procedure to achieve a selectedoperating condition. For example, hydrogen alone may be used toinitially heat the catalytic tubes 48 and achieve a selected operatingtemperature and then a mixture of hydrogen and other selected fuels suchas methane may be used for continuous operation or as an intermediary toa pure hydrocarbon or other selected fuel.

Nevertheless, using the gaseous hydrogen as the start-up fuel increasesthe kinetic activity thereby decreasing the temperature that thecatalytic tubes 48 must be at to achieve an optimum reaction of the fuelwith the oxidizer. Because the hydrogen may be able to react at a lowertemperature, yet optimally, with the catalyst in the catalytic tubes 48,the reaction may be able to heat the catalytic tubes 48 to a selectedtemperature that may be an optimal reaction temperature of a second fuelin the gas powered turbine 10. Therefore, a different fuel may be usedduring a start-up phase than a fuel used during a continuous operationor later phase. During the start-up phase, the catalytic tubes 48 areheated to a selected temperature to allow for the optimal operatingconditions of the gas powered turbine 10.

The use of two fuels may be used with substantially little difficulty ina single system. For example, and not intended to limit the description,a selected fuel may be natural gas, which may be used as a general andoperating fuel, while hydrogen gas may be used as a start-up fuel.During the start-up phase, the gaseous hydrogen may react with the otherportions of the gas powered turbine 10 in a substantially similar manneras the natural gas. For example, the hydrogen may be able to mix withthe hypergolic air by being injected through the main injector plate 52in a manner such that the gaseous hydrogen does not produce results thatare dissimilar to other selected fuels. For example, a fuel's injectionmomentum, G_(f) (ft.-lbm/sec₂), at a given heating rate, is defined bythe following equation:

$\begin{matrix}{G_{f} \propto \frac{{\hat{M}}_{f}}{P\;\Delta\; H_{c,f}^{2}}} & (1)\end{matrix}$where P is the main combustor compressor pressure (psi), {circumflexover (M)}_(f) is the molecular weight of the fuel (grams/mol) andΔH_(c,f) is the fuel's molar or volumetric heat of combustion (BTU/SCF).

The molecular weight and volumetric heating value of natural gas isapproximately 16 g/mol and 920 BTU/SCF, respectively. For hydrogen, themolecular weight and volumetric heating value is about 2 g/mol and 300BTU/SCF, respectively. Using Equation 1, at any given combustorpressure, the fuel momentum is substantially equivalent for the sameexcess air combustor firing rate. Therefore, the impingement jet mixturegeometry may allow for proper mixing for either the natural gas or thehydrogen, so that they may be easily interchanged such that either fuelmay be used to achieve substantially the same results in the gas poweredturbine 10.

Selected fuels may be substantially mixed with the heated oxidizerbefore the fuel combusts using various appropriate injectors. That is,that fuels that have substantially equivalent fuel injection momentums,as defined by Equation 1, may be used in similar injectors withoutchanging the injector geometry. Therefore, according to the exampledescribed above where natural gas and hydrogen has substantially similarinjector momentums, the injector will mix the fuel in a substantiallysimilar manner.

It will be understood, however, that not all combinations of fuels orpossibilities may include substantially similar injector momentums. Theinjector momentum may be easily determined, with Equation 1 or similarcalculations or experiments, and if the injector momentum issubstantially similar between two fuels or a plurality of fuels, thenthe injector may not need to be changed or altered to achieve similar orselected mixing. This allows that the combustor 14 may be operated usinga plurality of types of fuels without changing any of the physicalattributes, such as the injectors, of the combustor 14. This would allowa turbine 10 to remain in operation regardless of the fuel supply beingused or available to operate the combustor 14.

Thus, it will be understood that hydrogen need not simply be a start upfuel, and may be a fuel used to operate the combustor 14 duringoperation. That is a methane fuel source may be available at a certainpoint in the operating cycle of the combustor and/or a hydrogen fuelsource is available during a different operating cycle of the combustor14. Either of the fuels could be used to operate the combustor 14without changing any of the portions of the combustor 14. Simply, adifferent fuels may be run through the combustor 14.

With reference to FIG. 5, a schematic view of the start up system 18 anda plurality of the injectors 14 is illustrated. The premix chamber 20 isinterconnected with the ignition lines 22 that divide from the premixchamber 20 to each of the plurality of the combustors 14. Asillustrated, the line 22 may branch from a first main line 22 a to asecondary line 22 b into a plurality of individual lines 22 c. It willbe understood that any appropriate configuration of lines may beprovided and this is merely exemplary. For example, the main line 22 amay branch directly to the individual lines 22 c rather than having anintermediate line 22 b. Nevertheless, generally an individual line 22 cwill branch from a main line, either directly or indirectly. Therefore,anything emanating from the combustion wave chamber 20 may reach each ofthe combustors 14 at a substantially simultaneous time. In addition, itwill be understood that any number of the combustors 14 may be provided.Simply having six combustors is exemplary and not intended to limit thedescription.

Also, the combustion wave chamber 20 may be positioned at anyappropriate position relative to the combustors 14. For example, thecombustion wave chamber 20 may be provided on the turbine system 10 orprovided separately therefrom. Simply, the combustion wave chamber 20allows for a selective portion of a fuel to be combusted in an oxidizerto form a combustion wave as it propagates down the ignition lines 22.This allows the combustion wave chamber 20 to be provided at anyappropriate location that may be able to communicate with the ignitionline 22 to ignite the combustors 14 at a selected time. Therefore,providing it on the turbine 10 or in close proximity thereto is merelyexemplary and may be chosen for various reasons.

Turning reference to FIG. 6, the combustion wave chamber 20 and aselected portion of the ignition line 22 is illustrated. The combustionwave chamber 20 may be formed with any appropriate material or size, butmay include an exterior wall 80. The exterior wall 80 defines acombustion area or chamber 82 in which a selected fuel and oxidizer maycombust. A fuel inlet 84 is provided to allow a selected fuel to beinlet into the combustion chamber 82. The fuel may be any appropriatefuel, such as hydrogen or any selected hydro-carbon. For example,hydrogen may be used to allow for a substantially easy ignition andcomplete ignition of the fuel in the combustion chamber 82. In addition,the hydrogen may substantially eliminate any selected side reactionsduring the combustion of the fuel. The combustion wave chamber 20further includes an oxidizer inlet 86. The oxidizer inlet allows aninlet of any appropriate oxidizer, such as liquid or gaseous molecularoxygen. The oxidizer being oxygen is merely exemplary and anyappropriate oxidizer may be used. For example, the pure oxygen and thepure hydrogen may mix to substantially produce a selected combustionwave without producing selected side reactions.

Further provided on the combustion wave chamber 20 may be a sparkexciter 88. The spark exciter may include a plurality of spark exciters,such as a second spark exciter 90 may also be provided. The sparkexciters 88, 90 may be any appropriate exciter, such as a spark plug orother appropriate ignition source. In addition, the spark igniters 88,90 may be replaced by any appropriate ignition source and does notnecessarily require an electrical discharge. The spark exciters aremerely exemplary of a selected ignition source.

Once the selected volume of the oxidizer provided from the oxidizerinlet 86 and the fuel provided through the fuel inlet 84 is provided tocompletely fill combustion chamber 82 and downstream tube 100; theigniters 88, 90 may ignite the mixture to form a first combustion wave,that travels down tube 100 within ignition lines 22. Within a fewdiameters of tube 100 lengths, the slow deflagration combustion wavespeed quickly reaches detonation velocities approaching about Mach 2 toabout Mach 4. The gas pressure behind the combustion wave may becomeabout 10 to about 20 times higher than the gas pressure in front of thewave. It is generally known in the art that selected mixtures ofselected oxidizers and fuels may form a detonation wave. For example,the Chapman-Jougeut detonation theory as described in Williams, F. A.Combustion Theory, Addition-Wesley, Reading, Mass. (1965). Therefore,one skilled in the art will be able to determine a selected mixture ofoxidizer and fuel to produce the selected detonation wave as it travelsdown the ignition line 22.

The ignition line 22 may also generally include a selected volume of thefuel and the oxidizer, along which the detonation wave may propagate tothe pilot port 62 (FIG. 3). In addition, the ignition line 22 mayinclude a plurality of annuli. A first annulus may be an oxidizerannulus 92. The oxidizer annulus may be provided with a source ofoxidizer through an oxidizer annulus inlet 94. Also a fuel annulus 96may be provided near the oxidizer annulus 92 and provided with a sourceof fuel through a fuel annulus inlet 98. The fuel and the oxidizerprovided through the annuli 96, 92, respectively, provide the oxidizerand fuel source to keep a pilot lit at the pilot port 62 for a selectedperiod of time. The wave formed from the combustion of the oxidizer andthe fuel from the combustion chamber 82 propagates down a center annulus100 in the ignition line 22. Therefore, the detonation wave is provideddown a source that is substantially near the sources of the fuel andoxidizer that will be combusted by detonation wave to form the pilot.

According to various methods, the combustion chamber 82 is filled with astoichiometric volumes of the oxidizer and the fuel. For example, astoichiometric amount, such that complete combustion of the oxygen andthe hydrogen may form a selected product, may be placed in thecombustion chamber 82 after the combustion chamber 82 is filled with aselected stoichiometric amount of the oxidizer and the fuel, theigniters 88, 90 may ignite the stoichiometric mixture. Therefore, theamount or volume of the various components, including the oxidizer andthe fuel, in the combustion chamber 82 remain substantiallystoichiometric, prior to the ignition of the volume in the combustionchamber 82.

After the ignition of the volume in the combustion chamber 82 adeflagration wave is propagated out of the combustion chamber 82 anddown the wave transmission portion 100. After a certain number of lengthover diameters (L/D), the deflagration wave changes to a detonationwave. Generally the detonation wave travels at a speed that issubstantially supersonic down the transmission line 22. Once the wavereaches the exit of tube 100, its volume now contains a hot gas at about1648° C. to about 2760° C. (about 3000° F. to about 5000° F.) and apressure of about 10 to about 20 times higher than the pressure incombustion chamber 34. This high pressure causes the hot gas in tube 100to flow into chamber 34 for some period of time and ignite any flammablegas mixture residing there along with the pilot oxidizer and fuelflowing out of annuli 92 and 96.

The fuel and the oxidizer may be transmitted down the annuli 92, 96prior to the detonation of the mixture in the combustion chamber 82.Therefore, as soon as the detonation wave reaches the pilot port 62, thepilot will be ignited. Because each of the combustors 14 may include apilot port 62, each of the combustors 14 may be ignited substantiallysimultaneously. The pilot port 62 may be lit either before or after theoxidizer and the fuel have begun to flow into the combustor 14.

If the pilot is lit before the oxidizer and fuel flows into thecombustor 14, then substantially all flashback waves and other stressesmay be eliminated. Nevertheless, igniting each of the combustors 14substantially simultaneously may reduce such effects regardless.

Although the pilot may not be necessary during the operation of thecombustor 14, as described above, the oxidizer generally exits thecombustor tubes 48 at a hypergolic temperature of the fuel.Nevertheless, during selected procedures, it may be selected to includea pilot. For example, during start up of the turbine 10, it may beselected to provide a pilot to insure that the fuel is able to becombusted in the oxidizer even if the oxidizer has not yet achieved thehypergolic temperature. Therefore, it may be selected to provide thepilot into the combustion chamber 34 during the start up phase.

In addition, during operation of the turbine 10 or the combustor 14, itmay be selected, for various reasons, to provide a pilot in thecombustion chamber 34. Therefore, it will be understood that theignition system 18 may be used at any appropriate time and in anyappropriate manner. The ignition system 18 allows the single ignitionsource in the combustion chamber 82 of the combustion wave chamber 20 toprovide an ignition to each of the combustors 14 in the turbine 10substantially simultaneously. This may be done by providing a detonationwave that propagates down the ignition lines 22 to each of thecombustors 14 substantially simultaneously.

With reference to FIG. 7, a detailed portion of the combustor 14,similar to the portion illustrated in FIG. 3, according to variousembodiments of a heat exchanger 145 is illustrated. A premix chamber 142allows air from the compressor to be mixed with a first portion of fuel.Air comes from the compressor and travels through a cooling fin 144rather than through a plurality of cooling tubes 44, as discussed abovein relation to the first embodiment. It will be understood that exitports may also be formed in the cooling fins 144 to form the premix area142. The cooling fin 144 is defined by two substantially parallel plates144 a and 144 b. It will be understood, however, that other portions,such as a top and a bottom will be included to enclose the cooling fin144. Additionally, a heat exchange or catalyst fin 148 is providedrather than heat exchange tubes 48, as discussed above in the firstembodiment. Again, the catalyst fin 148 is defined by side, top, andbottom walls and defines a column 149. Each catalyst column 149,however, is defined by a single catalyst fin 148 rather than a pluralityof catalyst tubes 48, as discussed above. The cooling fin 144 mayinclude a plurality of cooling fins 144. Each cooling fin 144, in theplurality, defines a cooling pathway. Similarly, the heat exchange fin148 may include a plurality of heat exchange 148 fins. Each, or theplurality of, the heat exchange fins 148 defines a heat exchange orcatalyst pathway.

Channels 150 are still provided between each of the catalyst fins 148 sothat air may flow from the compressor through the cooling fins 144 intothe premix chamber 142. Air is then premixed with a first portion offuel and flows back through the catalyst fins 148 to the main injectorplate 152. Injection ports 160 are provided on the main injector plate152 to inject fuel as the air exits the catalyst fin 148. A suitablenumber of injection ports 160 are provided so that the appropriateamount of fuel is mixed with the air as it exits the catalyst fins 148.An intra-propellant plate 54 is also provided.

The injector ports 160 are provided on the main injector plate 152 toprovide fuel streams as heated air exits the oxidizer paths 172 from thecatalyst fins 148. Any appropriate injector ports may be used with thevarious embodiments of the heat exchanger 145 to provide a substantialmixing of the fuel with the air as it exits the catalyst fins 148. Thisstill allows a substantial mixture of the fuel with the air as it exitsthe catalyst fins 148 before the fuel is able to reach its ignitiontemperature. Therefore, the temperatures across the face of the maininjector 152 and in the combustion chamber 34 are still substantiallyconstant without any hot spots where NOX chemicals might be produced.

It will also be understood that the cooling fins 144 may extend into thepre-mixer 142 similar to the cooling tubes 44. In addition, ports may beformed in the portion of the cooling fins 144 extending into thepre-mixer to turn all the air exiting the cooling fins and mix with afirst portion of fuel.

It will be further understood that the heat exchanger, according to thepresent invention, does not require the use of individually enclosedregions or modular portions. Rather the heat exchanger may be formed ofa plurality of sheets, such as corrugated sheets. A first set of thesesheets may be oriented relative to one another to form a plurality ofcolumns. The first set of sheets include a catalyst coated on a sidefacing an associated sheet, such that the interior of the columnincludes the catalyst to contact the airflow. In this way, the catalystneed not be coated on the interior of a closed space, but rather thespace is formed after the catalyst is coated to form the catalystpathway. Operatively associated with the first set of sheets is a secondset of sheets, defining a second set of columns disposed at leastpartially between the first set of columns. Thus, the sheets may formthe fins to form the heat exchanger 145, heat exchange columns andcooling columns are formed. These then form the catalyst pathway and thecooling pathway in operation of the combustor.

A pilot port 62 may also extend from the combustor plate 152. Asdescribed above, the pilot port 62 may provide a means to ignite aselected fuel as it exits the catalyst pathways 148 and the fuel fromthe injectors 160. The pilot port 62 is substantially similar to thepilot port 62 in FIG. 3 and may be provided in various embodiments ofthe combustor or the heat exchanger 145.

With reference to FIG. 8, a combustor assembly 200 according to variousembodiments is illustrated. The combustor assembly 200 is generallyoriented along a central axis M. The combustor assembly 200 may includea pre-mix section 202, a pre-combustion or catalyst section 204, and amain combustion chamber or area 206. The main combustion chamber 206 isgenerally positioned downstream of an injector plate 208. The injectorplate 208 may be at least removable from the combustor assembly 200 foreasy changing and testing. The heat exchange tubes 48 also provide apathway for the hot oxidizer or hypergolic air, or air that becomeshypergolic, before it exits the main injector plate 208. Nevertheless,the heat exchange tubes 48 generally are interconnected with the maininjector plate 208 or a seal (not shown) to which the heat exchangetubes 48 are substantially brazed or fixed. The remaining portions ofthe combustor assembly 200 are substantially similar to the portionsillustrated in FIGS. 1 and 2.

The selected oxidizer and a first portion of the fuel is mixed in thepre-mix section 202, in an area of overlap or heat exchange that isformed where the cooling tubes 44 overlap the heat exchange tubes 48 inan overlap section 212. Although the shape of the combustor 200 may bedifferent than the shape of the combustor 14 illustrated in FIG. 2, thepurpose and operation may be substantially similar. Nevertheless, themain injector plate 208 may be easily removed from the combustorassembly 200 through a local main fuel supply port 214. The main fuelline 38 is interconnected to the main injector plate 208 through thefuel supply port 214. Therefore, rather than supplying the fuel throughthe center of the combustor 200, the fuel is provided near the maininjection plate 208 for easy removal of the main injector plate 208.

With continuing reference to FIG. 8 and additional reference to FIG. 9,where in FIG. 9 the outer portion of the combustor 200 has been removedto illustrate in detail the main injector plate 208. The main injectorplate 208 defines a plurality of oxidizer pathways 216 through which theheated oxidizer flows from the heat exchange tubes 48. The heatedoxidizer flows into the main combustion area 206 which is defined as thearea downstream of the downstream face 208 a of the main injector plate208. Fuel is provided to the areas between the oxidizer pathways 216through a plurality of injector plate fuel pathways 218. The maininjector plate fuel pathways 218 extend from the fuel port 214 to theareas between the oxidizer pathway 216 to injectors or the injectorelement 60.

With continuing reference to FIG. 9, the main injector plate 208 definesa plurality of the main injector plate fuel pathways 218 such that fuelmay be provided to each of a plurality of areas between the oxidizerpathways 216. The main injector plate 208 defines a thicknessappropriate to supply the fuel to the injection areas. The thickness ofthe injector plate 208 may be any appropriate thickness to meet variousrequirements. Nevertheless, the injector plate 208 provides the finalpathway for the fuel as it flows to the injector areas to be injectedinto the combustion area 206.

Because the fuel port 214 is interconnected with the injector plate 206,the main fuel line 38 may be disconnected and the injector plate 208removed from the combustor assembly 200. This may be done for anyappropriate reason, such as cleaning the injectors in the injector plate208, changing the injectors in the injector plate 208, or any otherappropriate reason. Therefore, the heat exchange tubes 48 may notgenerally be fixed to the main injector plate 206, but rather fixed to aseal or second portion that is able to substantially seal with or engagethe main injector plate 208 such that the oxidizers provided in theappropriate area.

The pilot port 62 may also be provided in the injector plate 208substantially similar to those described above. The pilot port 62 mayinclude a plurality of annuli that are defined through the injectorplates and extend along a ignition line 222 (a portion shown enlarged inFIG. 7 for clarity only). Therefore, the pilot fuel and oxidizer may beprovided along the annuli in the ignition line 222 that may be ignitedwith the detonation wave that is transmitted along the ignition line222. These portions may be formed in the main injector plate 208substantially similar to the lines defined in the fuel inlet lines 218.Nevertheless, the ignition line 222 may be formed at any manner in theinjector plates 208. The ignition line 222 may provide a path for thedetonation wave to detonate the selected oxidizer and fuel to form thepilot at the pilot port 62. Therefore, regardless of the configurationof the combustor 14, the pilot port 62 may provide a pilot at thecombustion chamber in the combustor 14. In addition, the ignition system18 allows for a substantially simultaneous ignition of a plurality ofthe combustors 14 without providing for a plurality of ignition sites inthe turbine 10. As discussed above, this may eliminate or reduce variousoccurrences, such as flashback high pressure changes and the like.

The present invention thus provides an apparatus and method thatvirtually or entirely eliminates the creation of NOX emissions.Advantageously, this is accomplished without significantly complicatingthe construction of the gas powered turbine 10 or the combustors 14.

The description of the invention is merely exemplary in nature and,thus, variations that do not depart from the gist of the invention areintended to be within the scope of the invention. Such variations arenot to be regarded as a departure from the spirit and scope of theinvention.

1. A power production system, comprising: a combustion oxidizer sourceto provide a selected volume of a combustion oxidizer; a combustion fuelsource to provide a selected volume of a combustion fuel; a plurality ofa combustor to combust the selected volume of the fuel and the oxidizer,wherein combusting the selected volume of the fuel and the oxidizer formexpanding gases; a turbine powered by the expanding gasses; and anignition system to provide substantially simultaneous ignition of eachof the plurality of the combustors, said ignition system including acombustion wave chamber to form a detonation wave that can betransmitted through an ignition line with at least one of a selectedoxidizer and a selected fuel.
 2. The power production system of claim 1,wherein: the plurality of the combustors each include a oxidizer pathwaythat provides a path to provide the oxidizer to main combustion chamberin each of the plurality of the combustors; and the selected volume ofthe combustion fuel is mixed with the selected volume of the oxidizerflowing to the oxidizer pathway to be combusted in the main combustionchamber.
 3. The power production system of claim 2, wherein saidignition system includes a pilot that is able to combust the selectedvolume of the combustion fuel in the selected volume of the combustionoxidizer.
 4. The power production system of claim 1, wherein: saidignition system includes a combustion wave chamber in which a selectedvolume of an ignition oxidizer in a selected volume of an ignition fuelis combusted; and the combustion of the selected volume of the ignitionoxidizer and the selected volume of the ignition fuel forms a detonationwave.
 5. The power production system of claim 4, wherein said ignitionsystem further includes an ignition line operable to transmit thedetonation wave from the combustion wave chamber to each of theplurality of the combustors substantially simultaneously.
 6. The powerproduction system of claim 1, wherein said ignition system includes anignition line, which includes a central tube to transmit the detonationwave, a first annulus to transmit the selected oxidizer and a secondannulus to provide the selected fuel.
 7. The power production system ofclaim 1, wherein: said ignition system includes a combustion wavechamber, an ignition line, and a pilot port; and said combustion wavechamber is operable to produce a combustion wave that is transmittedalong the ignition line to the pilot port.
 8. The power productionsystem of claim 1, further comprising an igniter to ignite a selectedvolume of an oxidizer and a fuel in the ignition system.
 9. The powerproduction system of claim 8, wherein said ignition source includes aspark source.
 10. A method of igniting a plurality of pilots in aplurality of main combustion chambers, each of said combustion chamberbeing separated from each of the other main combustion chambers, themethod comprising: forming a detonation wave; transmitting thedetonation wave to at least one of the main combustion chambers; atleast one of providing and flowing a selected volume of a pilot oxidizerand a pilot fuel to the main combustion chamber; igniting the selectedvolume of the pilot oxidizer and the pilot fuel; combusting a selectedmain fuel; and powering a turbine with the combusting main fuel.
 11. Themethod of claim 10, wherein forming a detonation wave includes: ignitinga selected volume of an oxidizer and a fuel, wherein the ignition formsthe detonation wave.
 12. The method of claim 11, wherein said oxidizeris molecular oxygen and said fuel is molecular hydrogen.
 13. The methodof claim 11, wherein igniting a selected volume of an oxidizer and thefuel includes spark igniting the selected volume of the oxidizer and thefuel at a selected time.
 14. The method of claim 10, further comprising:forming a deflagration wave; and transmitting the deflagaration wavealong a selected length of a transmission line to convert saiddeflagaration wave to the detonation wave.
 15. The method of claim 10,wherein transmitting the detonation wave to the at least one of the maincombustion chambers includes transmitting the detonation wave to aplurality of the main combustion chambers substantially simultaneously.16. The method of claim 15, wherein transmitting the detonation wave toa plurality of the main combustion chamber substantially simultaneouslyignites a plurality of pilots substantially simultaneously.
 17. Themethod of claim 16, wherein each of the plurality of the pilots combustthe selected main fuel substantially simultaneously in the plurality ofthe main combustion chambers.
 18. A power production system, comprising:a combustion oxidizer source to provide a selected volume of acombustion oxidizer; a combustion fuel source to provide a selectedvolume of a combustion fuel; a plurality of a combustor to combust theselected volume of the fuel and the oxidizer, wherein combusting theselected volume of the fuel and the oxidizer form expanding gases; aturbine powered by the expanding gasses; and an ignition system toprovide substantially simultaneous ignition of each of the plurality ofthe combustors, wherein said ignition system includes an ignition line,which includes a central tube to transmit the detonation wave, a firstannulus to transmit a selected pilot oxidizer and a second annulus toprovide a selected pilot fuel.